Floor burnishing apparatus with active dust control

ABSTRACT

A burnishing apparatus having at least one burnishing disc engageable with a floor includes a shroud surrounding the burnishing disc. The shroud defines a vacuum zone in fluid communication with a filtration system. The filtration system has an inlet, wherein the vacuum zone is in fluid communication with the inlet. In one embodiment, a vacuum source is in fluid communication with the inlet, wherein the vacuum source draws dust from the vacuum zone into the filtration system through the inlet, and at least some of the dust is collected by the filtration system. In another embodiment of the invention, an agitation device regenerates at least one filter element forming part of the filtration system.

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] This application claims the priority benefit of U.S. Provisional Patent Application No. 60/417,930 filed on Oct. 11, 2002.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] Not Applicable.

BACKGROUND OF THE INVENTION

[0003] The field of invention is floor burnishing equipment, and more particularly, a floor burnishing apparatus having an active dust control system.

[0004] Floor burnishing equipment typically includes a rotating disc which polishes a floor to produce a high gloss finish. The disc removes a thin layer of the floor finish to produce the smooth glossy appearance. The thin layer is removed in the form of a fine powder. Air turbulence caused by the rotation of the disc can disperse the fine powder into the air. The fine powder then settles on the floor, walls, and surrounding furniture which must be cleaned following the burnishing operation.

[0005] In order to limit the dispersal of the powder, burnishing equipment having a passive dust collection system, such as disclosed in U.S. Pat. No. 4,939,811, have been developed which incorporate the air currents generated by the rotating burnishing disc surrounded by a shroud to propel the powder into a paper sock-type collection filter disposed tangential to the rotating disc. Unfortunately, the collection filter must be changed often to prevent the filter from being clogged. Moreover, the powder disposed in the shroud when the disc ceases to rotate falls to the ground and requires additional efforts to remove.

[0006] Floor burnishing equipment having an active dust collection system, such as disclosed in U.S. Pat. No. 2,663,893, have been developed which include a vacuum system that propels the dust into a sock-type collection filter. As in the passive dust collection systems, the filter must be changed on a regular basis to prevent the filter from being clogged. Moreover, in the prior art active dust collection systems, the abrasive dust passes through the vacuum system which increases maintenance of the vacuum system and can cause premature failure of the vacuum system components.

[0007] In addition, the paper filter sock-type filters not only have a limited capacity, they support bacteria which can cause the filter to deteriorate prior to reaching its dust capacity. Moreover, deterioration of the paper filter is accelerated if it becomes wet. Accordingly, a need exists for a burnishing machine having an improved dust collection system.

BRIEF SUMMARY OF THE INVENTION

[0008] The present invention provides a burnishing apparatus having at least one burnishing disc engageable with a floor. A shroud surrounds the burnishing disc and defines a vacuum zone in fluid communication with a filtration system. The filtration system has an inlet, wherein the vacuum zone is in fluid communication with the inlet. In one embodiment, a vacuum source is in fluid communication with the inlet, wherein the vacuum source draws dust from the vacuum zone into the filtration system through the inlet, and at least some of the dust is collected by the filtration system. In another embodiment of the invention, an agitation device regenerates at least one filter element forming part of the filtration system.

[0009] A general objective of the present invention is to provide a burnishing apparatus having an improved filtration system that collects dust created by the burnishing disc. This objective is accomplished by providing a burnishing apparatus having an active dust collection system.

[0010] Another objective of the present invention is to provide a burnishing apparatus that has a long lasting filter element. This objective is accomplished by providing a burnishing apparatus with a dust collection system having a filter element that can be regenerated to prolong the useful life of the filter element.

[0011] Yet another objective of the present invention is to provide a burnishing apparatus with an active dust collection system having a vacuum source that is not subjected to constant erosion by the dust. This objective is accomplished by providing a burnishing apparatus having an active dust collection system that draws the dust into a filter element to clean the air prior to passing through the vacuum source.

[0012] The foregoing and other objectives and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a front, right side perspective view of a burnishing machine incorporating the present invention;

[0014]FIG. 2 is a front, left side perspective view of the burnishing machine of FIG. 1;

[0015]FIG. 3 is a bottom view of the burnishing machine of FIG. 1;

[0016]FIG. 4 is a right side elevation view of the burnishing assembly and dust collection system of the burnishing machine of FIG. 1;

[0017]FIG. 5 is a detailed view of the burnishing assembly and dust collection system of FIG. 4 fixed to the chassis;

[0018]FIG. 6 is a left, front perspective view of the burnishing assembly of FIG. 5;

[0019]FIG. 7 is a bottom view of the burnishing assembly of FIG. 6;

[0020]FIG. 8 is a left, front perspective view of the filter enclosure of FIG. 5;

[0021]FIG. 9 is a rear view of the filter enclosure of FIG. 8;

[0022]FIG. 10 is a right end view of the filter enclosure of FIG. 8;

[0023]FIG. 11 is a cut away, front, right side perspective view of the burnishing assembly and dust collection system of FIG. 4;

[0024]FIG. 12 is a cut away, rear, left side perspective view of the dust collection system of FIG. 4;

[0025]FIG. 13 is a cut away, bottom, right side perspective view of the dust collection system of FIG. 4;

[0026]FIG. 14 is side view of portions of the burnishing machine of FIG. 1 with an alternative burnishing system;

[0027]FIG. 15 is a perspective view of the burnishing system of FIG. 14; and

[0028]FIG. 16 is a bottom view of the burnishing system of FIG. 15.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] As shown in FIGS. 1-4 and 11, a burnishing machine 10, or apparatus, includes a burnishing assembly 12 and an active dust collection system 14. The burnishing assembly 12 polishes a floor which creates dust. The dust collection system 14 includes a vacuum source 16 which draws the dust created by the burnishing assembly 12 through a filtration system 18 having filter elements 78. The filtration system 18 collects the dust in the filter elements 78 upstream of the vacuum source 16 to minimize maintenance.

[0030] The burnishing machine 10 includes a chassis 20 having a front end 22 and a rear end 24 joined by sides 26. The chassis 20 supports a body 28 and filtration system 18, and is in turn supported by floor engaging rear wheels 30 and a front steerable wheel 32. The steerable wheel 32 is operatively connected to a steering wheel 34 through the chassis 20 proximal the chassis front end 22. A driver seat 38 is supported by the filtration system 18 rearward of the steering wheel 34 for use by an operator operating the burnishing machine 10. The operator sits on the driver seat 38 to operate the steering wheel 34 and foot operated control pedals 40, such as a brake and accelerator supported above the chassis top surface 42.

[0031] The body 28 houses a plurality of batteries (not shown) which provide electrical power to an electric drive motor 36 coupled to the streerable wheel 32. The batteries also provide electrical power to the burnishing assembly 12 and other electrical components described below. The drive motor 36 rotatably drives the steerable wheel 32 to propel the burnishing machine 10 along the floor. Although an electric motor powered by the batteries for rotatably driving the steerable drive wheel 32 is preferred, the drive wheels 30 can be electrically driven, an/or the steerable wheel 32 can be driven by other means, such as an internal combustion engine powered by gasoline, natural gas, and the like, without departing from the scope of the invention.

[0032] The chassis 20 also supports a control panel 43 within reach of the operator sitting on a driver seat 38 and proximal one of the chassis sides 26. The control panel 43 houses circuitry for controlling the drive motor and the other electrical components described below. Control circuitry for controlling motors, pumps, and other electrical components is known in the art, such as control circuitry available on TOMCAT cleaning equipment available from Mid-Central Corporation in Racine, Wis. Although a drivable burnishing machine is disclosed, the burnishing machine can be a walk behind type without departing from the scope of the invention.

[0033] Side guards 39 fixed to each side 26 of the chassis 20 include ground engaging strips 41. The strips 41 include a ground engaging edge 43 which further contain dust from dispersing transversely past the chassis sides 26. The strips 41 are preferably formed from a flexible material, such as rubber, flexible plastic, bristles, and the like, and are clamped onto a support bracket 45 to form the guard 39. The support bracket 45 is fixed to the chassis 20 using fasteners, such as bolts, screws, and the like.

[0034] Access panels 47 fastened to the chassis 20 can be provided to protect the components beneath the chassis 20 and provide access thereto. The panels 47 can be formed from any suitable material, such as metal, rigid plastic, fiberglass, and the like, and can be hingedly or detachably fixed to the chassis 20 using methods known in the art.

[0035] As shown in FIGS. 5-7, the burnishing assembly 12 is disposed beneath the chassis 20, and includes a pair of burnishing discs 44 engageable with the floor for polishing the floor. Each disc 44 is coupled to a vertical shaft 46 extending from an electric motor 48 which rotatably drives the disc 44. The vertical shafts 46 extend downwardly through a support plate 50 which supports the motors 48 and discs 44 over the floor. Although a pair of burnishing discs 44 is disclosed, one or more burnishing discs can be provided without departing from the scope of the invention.

[0036] The support plate 50 is supported from the chassis 20 by pivotable support arms 52 pivotally connected to each side 53 of the support plate 50. The pivotable support arms 52 allow the support plate 50 to move between an upper position and a lower position. In the upper position, the support plate 50 is spaced above the floor a sufficient distance to disengage the burnishing discs 44 from the floor. In the lower position, the support plate 50 is spaced above the floor a distance such that the burnishing discs 44 are engaged with the floor.

[0037] A lifting bracket 54 pivotally connected to a center rib 55 forming part of the support plate 50 connects to a cable 55 which raises and lowers the support plate 50 between the upper and lower positions. The cable 55 is connected to an electric actuator 51 which is operable by the operator to raise and lower the support plate, and thus selectively engage and disengage the burnishing discs with the floor. Of course, the cable can be connected to a manual actuator, such as a lever, without departing from the scope of the invention. Advantageously, the electric actuator 51 can be controlled by the control circuitry to control the tension in the cable 55, and thus the pressure exerted on the floor by the burnishing discs 44 during the burnishing operation.

[0038] An inner shroud 56 surrounds the burnishing discs 44 to prevent dust generated by the burnishing discs 44 from dispersing into the atmosphere. The inner shroud 56 defines an inner vacuum zone 58 for the dust collection system 14, and is fixed to a frame 57 fixed relative to the support plate 50. Preferably, the inner shroud 56 is formed from a flexible material, such as rubber, flexible plastic, bristles, and the like. A lower edge 60 of the inner shroud 56 engages the floor, and forms a barrier which prevents dust from dispersing into the atmosphere.

[0039] The frame 57 is fixed to the support plate 50 using conventional fasteners 59, and is formed from one or more pieces of a rigid material, such as metal, rigid plastic, fiberglass, and the like. Advantageously, the frame 57, and thus the inner shroud 56 is raised and lowered with the support plate 50, as the support plate 50 moves between the upper and lower positions.

[0040] A shelf 64 extends inwardly from the frame 57, and is, preferably fixed to the support plate 50 by the fasteners 59. Suction ports 68 formed through the shelf 64 are sealingly connected to hoses 70 connected to the filtration system 18. The ports 68 define openings through the shelf 64 into the vacuum zone 58. Although a frame having a shelf connected to the support plate is disclosed, the support plate and frame can be formed from a single piece without departing from the scope of the invention. Moreover, the frame can also be independent of the support plate, such that the frame is fixed relative to the chassis without departing from the scope of the invention.

[0041] Referring back to FIG. 3, an outer shroud 61 surrounds the inner shroud 56 to further contain dust created during the burnishing operation within an outer vacuum zone defined by the outer shroud 61. The outer shroud 61 includes the side guard strips 41 extending downwardly from each side 26 of the chassis 20. A forward strip 63 and a rearward strip 65 join the side guard strips 41 to surround the inner shroud 56. The forward and rearward strips 63, 65 can be formed from the same material as the inner shroud 56, and are fixed relative to the chassis using methods known in the art, such as fasteners. Although both inner and outer shrouds 56, 61 are disclosed, the burnishing machine 10 can be provided without one of the shrouds 56, 61, such as, for example, shown in FIGS. 14-16 and described below, without departing from the scope of the invention.

[0042] The active dust collection system 14 collects dust generated by the burnishing assembly 12, and includes the vacuum source 16 which draws the dust from the vacuum zone 58 into the filtration system 18. As shown in FIGS. 4, 8-13, the filtration system 18 disclosed herein is a baghouse filter system having a filter enclosure 76 enclosing the plurality of filter elements 74 hanging from a filter hanger 81. Air and dust is drawn into the filter enclosure 76 by the vacuum source 16 disposed downstream of the filter elements 74 to minimize damage to the vacuum source 16 caused by the dust.

[0043] Referring to FIGS. 8-10, the filter enclosure 76 includes a rectangular enclosure box 80 having an open top 82 and closed bottom 84 joined by sides 86 and ends 88. The top 82 is defined by the upper edges of the sides 86 and ends 88, and is closed by a cover 90 detachably fixed to the sides 86. A pair of enclosure inlets 92 formed through one of the sides 86 proximal the box bottom 84 are in fluid communication with the vacuum zone 58 through the suction ports 68 via the hoses 70.

[0044] One end of the rectangular box 80 includes a cutout 93 proximal the box bottom 84 for receiving a removable tray 94 slidably inserted into the filter enclosure 76 for collecting dust. Dust drawn into the filter enclosure 76 settles on the removable tray 94 for later disposal. The tray 94 includes a face panel 96 which abuts an exterior surface of the box end 88 when the tray 94 is fully inserted into the filter enclosure 76. Of course, sealing material, such as a gasket, fixed to the face panel 96 or box end 88 can be provided which engages the exterior surface of the box end 88 or the interior surface of the panel 96 to seal the cutout 93 when the tray 94 is fully inserted into the filter enclosure 76. A handle 97 and latch can also be provided in the face panel 96 for grasping by the operator sliding the tray 94 out of the filter enclosure 76.

[0045] The cover 90 closes over the box top 82, and includes a planar top 98 having sides 100 and ends 102 extending downwardly from the planar top periphery. The cover sides 100 and ends 102 are aligned with the box sides 86 and ends 88 to close the box top 82. A pair of latches 104 pivotally fixed to each cover side 100 engages catches fixed to each box side 86 to detachably fix the cover 90 to the box 80. Of course, an elastomeric gasket material, such as rubber, flexible plastic, and the like, can be sandwiched between the box 80 and cover 90 to form an air tight seal between the cover and box. An enclosure outlet 108 is formed in one of the cover sides 100, and is in fluid communication with the vacuum source 16. An opening formed in the cover top 98 is closed by a hinged access panel 110 which allows inspection of the filter elements 78 without detaching the cover 90 from the box 80.

[0046] As shown in FIGS. 11-13, the filter hanger 81 is disposed in the box 80, and fixed relative to the box 80 proximal the box top 82. Preferably, the filter hanger 81 is formed from a rigid substantially planar material, such as metal, rigid plastic, fiberglass, and the like. The hanger 81 includes a plurality of spaced longitudinal slots 114 which allow air to pass through. Preferably, air passing through the filtration system 18 must pass through one of the slots 114 to exit the filter enclosure 76 through the enclosure outlet 108. One of the filter elements 78 hangs through each slot 114, and is interposed between the enclosure inlet 92 and enclosure outlet 108.

[0047] The filter elements 78 trap dust drawn into the filtration system 18 to inhibit the dust from exiting through the enclosure outlet 108 into the vacuum source 16. Each filter element 78 is preferably formed from a polymer felt material which traps a higher volume of dust than the prior art paper filter elements. Moreover, the polymer felt material does not support bacteria growth which can deteriorate the filter element. Although a filter element 78 formed from a polymer felt material is disclosed, any filter material known in the art, such as paper, and the like, which can trap dust can be used. In addition, although a plurality of individual filter elements is disclosed, one or more filter elements can be provided without departing from the scope of the invention. In fact, a single filter element, such as a vortex dust separator, can be provided without departing from the scope of the invention.

[0048] In the preferred embodiment, each filter element 78 hanging through one of the plurality of spaced longitudinal slots 114 forms a loop having facing filter material 124. Each loop extends toward the bottom 84 of the enclosure box 80 and terminates above the enclosure inlets 92. A rod 122 suspended by the filter material in each loop weighs down the filter element 78 to maximize the filtration area defined by the exposed surface area of the facing filter material 124. An aperture 126 formed through each filter element 78 at the bottom of the loop exposes the rod 122 for engagement with an agitation device 130.

[0049] An air spacer 132 inserted into the loop of each filter element 78 between the facing filter material 124 separates the facing filter material 124 of each filter element 78. The air spacer 132 is preferably formed from a porous foam which allows air to pass through. Advantageously, the air spacer 132 prevents the facing filter material 124 from being drawn together by the vacuum source 16 which reduces the effective filtration area of the filter element 78.

[0050] The agitation device 130 includes a rotatably driven paddle 134 that engages the exposed rods 122 to shake the filter elements 78 and dislodge dust trapped therein. Advantageously, the dislodged dust falls into the tray 94 for later disposal. The paddle 134 extends between the box sides 86, and is rotatably driven by an electric motor 136 mounted to the box side 86 outside of the filter enclosure 76. The motor 136 is coupled to the paddle 134 by a gear box 138 which allows mounting the motor 136 at a right angle relative to the paddle axis of rotation. Walls 139 (shown in FIG. 10) fixed to the box side 86 enclose the motor 136, and protect it from damage.

[0051] The agitation device 130 regenerates the filter elements 78 to provide a filtration system 18 having a substantially unlimited dust capacity and which does do not normally require replacement of filter elements 78 during the useful life of the burnishing machine 10. Although, an agitation device having a paddle which shakes the filter material is disclosed, any agitation device that can dislodge dust trapped by the filter material can be used, such as an air back flow device that reverses the flow of air through the filter element, a shaker device that shakes the filter hanger, and the like, can be provided without departing from the scope of the invention.

[0052] The vacuum source 16 is, preferably, a centrifugal fan having a rotatably driven impellor (not shown) surrounded by a fan housing 140. An electric motor 142 mounted adjacent to the fan housing 140 rotatably drives the impellor. The fan housing 140 and motor 142 are fixed to the chassis 20 rearwardly of the filtration system 18 in the machine body 28 using brackets 144. The centrifugal fan housing 140 includes an inlet 146 and an outlet 149. The impellor creates a suction at the inlet 146 by propelling air in the fan housing 140 through the outlet 149. Although a centrifugal fan is preferred, any type of vacuum source can be used, such as a vacuum pump, radial fan, piston pump, and the like, without departing from the scope of the invention.

[0053] The housing inlet 146 is connected to the enclosure outlet 108 via hose 148 to draw air through the filtration system 18. As a result, dust in the vacuum zone 158 is drawn into the filtration system 18 and captured by the filter elements 78 before the dust can damage the vacuum source 16. Air passing through the filter elements 78 is drawn into the fan housing inlet 146, and subsequently propelled by the impellor through the housing outlet 149 into the machine body 28. Advantageously, expelling the filtered air into the body 28 minimizes noise and circulates air over the batteries to expel noxious fumes generated by the batteries in the body 28.

[0054] Referring to FIGS. 1-13, in use, the burnishing machine 10 can operate in a burnishing mode or a transport mode. In the burnishing mode, the support plate 50 is lowered to its lower position, such that the burnishing discs 44 engage the floor. The burnishing discs 44 are rotated by the respective motors 48 to remove a thin layer of finish off of the floor in the form of dust which is substantially contained within the vacuum zone 58. The dust is drawn out of the vacuum zone 58 through the suction ports 68 into the filtration system 18 by the vacuum source 16, and trapped in the filter elements 78 hanging in the filter enclosure 76. Air drawn through the filtration system 18 is expelled into the machine body 28 by the vacuum source 16.

[0055] Dust collected in the filter enclosure 76 settles into the removable tray 94 disposed proximal the bottom 84 of the enclosure box 80 for later disposal. Upon completion of the burnishing operation, dust lodged in the filter elements 78 is dislodged by the agitation device 130 which shakes the filter elements 78 to cause the dust to fall into the tray 94. Periodically, the tray 94 is slid out of the filter enclosure 76, and the dust is deposited into a waste container, or other receptacle.

[0056] In the transport mode, the support plate 50 is raised to its upper position, such that the burnishing discs 44 are disengaged from the floor. Advantageously, in the transport mode, the burnishing machine 10 can be moved between locations without damaging the burnishing discs 44.

[0057] In an alternative embodiment, the burnishing machine 10 can be used as a buffing machine to provide a restorative finish on the floor. In order to buff a floor using the burnishing machine, the rotational speed of the burnishing disc is reduced to less than 400 RPM to work a finishing solution into cracks and imperfection in the floor. Preferably, the burnishing machine used for buffing includes an onboard tank containing a finishing solution, such as a spray buff chemical, which is sprayed onto the floor prior to buffing the floor with the burnishing disc. In one embodiment, the onboard tank is in fluid communication with a spray nozzle using a hose. The spray nozzle is supported by the chassis forward of the buffing disc, such that the spray nozzle sprays the finishing solution onto the floor prior to buffing the floor with the burnishing disc.

[0058] The burnishing machine 10 can be provided with an alternative preferred burnishing assembly 212, such as shown in FIGS. 14-16, that does not include an inner shroud. As in the burnishing assembly 12 disclosed in FIGS. 5-7, the alternative burnishing assembly 212 is disposed beneath the chassis 20 and is surrounded by the outer shroud 61. The burnishing assembly 212 includes at least one burnishing disc 244 engageable with the floor for polishing the floor. Each disc 244 is coupled to a vertical shaft 46 extending from an electric motor 248 which rotatably drives the disc 244. The vertical shafts 246 extend downwardly through a support plate 250 which supports the motors 248 and discs 244 over the floor.

[0059] The support plate 250 is supported from the chassis 20 by pivotable support arms 252 pivotally connected to each side 253 of the support plate 250. The pivotable support arms 252 allow the support plate 250 to selectively move between an upper position and a lower position. In the upper position, the support plate 250 is spaced above the floor a sufficient distance to disengage the burnishing discs 244 from the floor. In the lower position, the support plate 250 is spaced above the floor a distance such that the burnishing discs 244 are engaged with the floor. A lifting bracket 254 pivotally connected to a center rib 255 forming part of the support plate 250 can connect to a cable, such as the cable 55 disclosed above, which raises and lowers the support plate 50 between upper and lower positions.

[0060] Height adjustable forward and rearward inner strips 257, 259 can be provided that are adjustably fixed to a leading and trailing edge 261, 263 of the support plate 250. The strips 257, 259 are preferably formed from a flexible material, such as rubber, flexible plastic, bristles, and the like. A lower edge 260 of each strip 257, 259 engages the floor, and forms a barrier which helps prevent dust from dispersing rearwardly or forwardly toward the outer shroud 61 and into the atmosphere. Each of the forward and rearward strips 257, 259 can include tabs 261, 263 that can abut the outer shroud 61.

[0061] While there have been shown and described what is at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention defined by the appended claims. 

I claim:
 1. A burnishing apparatus comprising: at least one burnishing disc engageable with a floor; a shroud surrounding said burnishing disc defining a vacuum zone; a filtration system having an inlet, wherein said vacuum zone is in fluid communication with said inlet; a vacuum source in fluid communication with said inlet, wherein said vacuum source draws dust from said vacuum zone into said filtration system through said inlet, and at least some of said dust is collected by said filtration system.
 2. The burnishing apparatus as in claim 1 including a chassis and at least one floor engaging wheel supporting said chassis above the floor, wherein said at least one floor engaging wheel is rotatably driven to propel said chassis along the floor, and said at least one burnishing disc is disposed beneath said chassis.
 3. The burnishing apparatus as in claim 2, in which said filtration system includes a filter enclosure, and said filter enclosure supports a driver seat above said chassis.
 4. The burnishing apparatus as in claim 1, in which said filtration system includes at least one filter element which collects dust passing through said inlet.
 5. The burnishing apparatus as in claim 4, including an agitation device engageable with said at least one filter element to dislodge dust collected by said at least one filter element.
 6. The burnishing apparatus as in claim 4, in which said filtration system includes a removable tray disposed beneath said at least one filter element for collecting dust drawn into said filtration system.
 7. The burnishing apparatus as in claim 4, in which said at least one filter element is formed from a polymer felt material.
 8. The burnishing apparatus as in claim 1, in which said vacuum source is a centrifugal fan.
 9. The burnishing apparatus as in claim 1, in which said shroud includes an inner shroud surrounded by an outer shroud.
 10. A burnishing apparatus comprising: at least one burnishing disc engageable with a floor; a shroud surrounding said burnishing disc defining a vacuum zone; a filter enclosure having an inlet and an outlet, said inlet being in fluid communication with said vacuum zone; and at least one filter element disposed in said filter enclosure and interposed between said inlet and said outlet.
 11. The burnishing apparatus as in claim 10, including a chassis and at least one floor engaging wheel supporting said chassis above the floor, wherein said at least one floor engaging wheel is rotatably driven to propel said chassis along the floor, and said at least one burnishing disc is disposed beneath said chassis.
 12. The burnishing apparatus as in claim 11, in which said filter enclosure supports a driver seat above said chassis.
 13. The burnishing apparatus as in claim 10, including an agitation device engageable with said at least one filter element to dislodge dust collected by said at least one filter element.
 14. The burnishing apparatus as in claim 10, in which a removable tray is disposed in said filter enclosure beneath said at least one filter element for collecting dust entering said filter enclosure through said inlet.
 15. The burnishing apparatus as in claim 10, in which said at least one filter element is formed from a polymer felt material.
 16. The burnishing apparatus as in claim 10, in which a vacuum source is in fluid communication with said outlet to draw dust into said filter enclosure through said inlet.
 17. The burnishing apparatus as in claim 16, in which said vacuum source is a centrifugal fan.
 18. The burnishing apparatus as in claim 10, in which said filter enclosure has a cover which provides access to said at least one filter element.
 19. The burnishing apparatus as in claim 10, in which said shroud includes an inner shroud surrounded by an outer shroud.
 20. A method of burnishing a floor, said method comprising: engaging a floor with at least one rotatably driven burnishing disc surrounded by a shroud, wherein said shroud defines a vacuum zone; drawing dust created by said rotatably driven burnishing disc engaging the floor into a filtration system in fluid communication with said vacuum zone; and separating said dust from air drawn into said filtration system.
 21. The method as in claim 20, in which separating said dust includes drawing said air through at least one filter element which traps at least some of said dust.
 22. The method as in claim 21, including dislodging dust from said at least one filter element, and collecting said dislodged dust for disposal. 